Systems and methods for sub-aperture based aberration measurement and correction in interferometric imaging
AssigneeCarl Zeiss Meditec AG
InventorsAbhishek Kumar, Alexandre R. Tumlinson, Rainer Leitgeb
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Abstract
Systems and methods for sub-aperture correlation based wavefront measurement in a thick sample and correction as a post processing technique for interferometric imaging to achieve near diffraction limited resolution are described. Theory, simulation and experimental results are presented for the case of full field interference microscopy. The inventive technique can be applied to any coherent interferometric imaging technique and does not require knowledge of any system parameters. In one embodiment of the present application, a fast and simple way to correct for defocus aberration is described. A variety of applications for the method are presented.
Claims25
A method for characterizing a wavefront in interferometric imaging data on a sample, wherein the interferometric data is generated using a broad bandwidth light source wherein the interferometric data contains information about lateral structure within the sample, said method comprising:
- generating a beam from the broad bandwidth light source;
- dividing the beam into reference and sample arms wherein the sample arm contains the sample to be imaged;
- directing the beam to the sample;
- combining light scattered from the sample and light returning from the reference arm;
- detecting the combined light and generating signals in response thereto;
- processing the signals to isolate an axial subset of the interferometric data corresponding to a depth in sample where the lateral structure is located;
- dividing the axial subset into lateral subsections at a plane where the wavefront should be characterized;
- determining a correspondence between at least two of the lateral subsections;
- characterizing the wavefront using the correspondence;
- and
- storing or displaying the wavefront characterization, or using the wavefront characterization as input to a subsequent process.
A system for characterizing a wavefront in interferometric imaging data of a light scattering object containing lateral structure comprising:
- a broadband light source arranged to generate a beam of radiation;
- a beam divider for separating the beam into reference and sample arms, wherein the sample arm contains the light scattering object to be imaged;
- optics to direct said beam of radiation on the light scattering object to be imaged and for combining light scattered from the object and light returning from the reference arm;
- a detector for recording the combined light and generating signals in response thereto;
- and
- a processor for isolating an axial subset of the generated signals corresponding to a depth in the sample where the lateral structure is located, dividing the axial subset into lateral subsections at plane where the wavefront should be characterized, said processor further for determining a correspondence between at least two of the subsections, and for using the correspondence to characterize the wavefront.
Dependencies are inferred from the claim text.